I was playing Bitcoin Darts Today and it has taken over 3 hrs to receive 1 unconfirmed payment of many.Just wondering - In general how long it should take to receive a payment and what have people been experiencing.

There is only limited amount of free transactions every hour. As Bitcoin popularity is going up, those slots are full time to time. To speed up transaction processing, you can offer some fee in the client settings. Then the transaction will be included ASAP.